Bubble play is one of the most favored activities of my son, and needless to say I love it too. As a child I loved bubble play and am happy to see that my son has taken a liking to it as well.
I bought the bubble play set from Toys r Us, and also the liquid required.
We would play bubbles because it was fun, little did I know that it has so many benefits. I got to know of them when I saw that at Gymboree they use bubbles play as an integral part of their play-gym class. The teacher blows small bubbles and all the children run up to burst as many as they can or then try to catch one on their finger. After this the children sit with their parent and the teacher comes around to each child and blows him bigger bubbles which the child is supposed to burst saying 'pop', during this exercise everyone is singing "bubbles for xyz" for every child there is. This makes the child feel special and at the same time he gains confidence of being in a group.
I also read that the child manages to use complex mouth movement, blowing air out, keeping tongue at a certain position etc in order to blow bubbles. The child picks up language as we tell them to say 'pop goes the bubble' etc. And with the complex mouth movements required to blow bubbles, they learn to move the tongue to make different sounds thus improving language skills. With bubbles we can also teach them what a circle is or what the difference between a sphere and circle is. Numerical games can also be done with use of bubble-play.
With my son we have discovered that he loves to play bubbles during his bath where he has another of his favorite play item - water. When he was younger, where in he would bathe in a tub I would make a bubble bath for him and he would love them. I used the liquid soap by Kodomo for this purpose, this one had moisterisers so that the baby skin is not damaged due to the longer duration in water. Now that he is older and loves the shower, we play bubbles using all the different shape blowers (as seen in the picture above) and enjoy the time, this way I am spared the trouble of mopping the floors after a bubble play and my son gets to do his favorite stuff.